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|---|---|---|---|---|---|---|---|---|---|---|
6byy2o
|
Why can Parrots talk? Can they only repeat what people say, or can they formulate their own thoughts and vocalize them sometimes?
|
Biology
|
explainlikeimfive
|
[
"dhqniqw",
"dhqppx2",
"dhqm5dn",
"dhrqi5q"
] |
[
"It depends on the type of parrot. Some parrots will just mimik, others can understand context as well. When training a parrot simply saying \"Hello\" to it over and over again will get teach your parrot how to say \"Hello\". When you come home everynight and say \"Hello\", the parrots starts understanding the context of when to say \"Hello\". My parrot will say \"Good Morning\", \"Good Bye\", \"Hello\", and \"Good Night\" very clearly during the right times of day. Smarter parrots will start understanding context from interactions between two individuals. My parrot picked up on, \"What are you doing?\" and \"Where are you going?\" from me asking my SO those questions. We would always explain to him whenever he asked those questions, even though he probably didn't understand. The story that I usually tell to convey how smart my bird is, is such: After I graduated college I woke up first, and went to work. My parrot would say good morning and good bye to me at the respective times. My SO would stay at home most of the morning then attend grad school in the evening. Once she graduated from grad school, she actually had to leave earlier than me for her job. The first day she woke up earlier than me my parrot freaked out. He started yelling \"What are you doing?!\" as she was taking her shower. When she started to get ready to leave (coat, shoes, keys) He started yelling \"Where are you going?!\" For me, he would just say Good Morning, and Good Bye. I think he liked her better than me."
] |
[
81
] |
[
[],
[
"https://en.wikipedia.org/wiki/Alex_\\(parrot\\)"
],
[],
[
"http://www.avianwelfare.org/"
]
] |
[
"url"
] |
[
"url"
] |
|
9eyq7p
|
if testosterone and estradiol (hormones) control growth in your body during puberty, is it possible to inject these hormones to promote extra growth? Do people do this? What are the repercussions?
|
Biology
|
explainlikeimfive
|
[
"e5sgtqe"
] |
[
"Many hormones have multiple roles in the body. Adding too much of one hormone might cause one (desired) effect, with other (undesired) side effects. For example, extra estradiol can both prevent pregnancy and cause weight gain. People inject testosterone and estradiol already--they're both big parts of trans* therapies. In adults, they don't cause long bone growth, likely because the body is done growing and the injections of these hormones doesn't undo that. Some people do have extra growth hormone (and it's called that, GH) in their bodies. These people have \"gigantism\" or \"acromegaly\". They tend to be tall if they start making too much GH as children (while they're still growing), but even if the body starts making GH later they also have large heads/hands/faces, and other problems with their bodies. The growing head can put pressure on the nerves from the eye, and people can go blind. Adding extra GH isn't usually a good idea, but [some people do it anyway]( URL_0 )."
] |
[
7
] |
[
[
"https://en.wikipedia.org/wiki/Growth_hormone#Medical_uses"
]
] |
[
"url"
] |
[
"url"
] |
|
fe1js6
|
How does RAM work and what is it’s purpose?
|
Technology
|
explainlikeimfive
|
[
"fjl5pz7",
"fjl61bt"
] |
[
"I think of RAM as similar as short term memory in humans. Its the little things that you access on a frequent basis that are stored there, but also things that are stored there can be erased if it no longer used."
] |
[
5
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
77mts0
|
If bones can heal itself, Why cant our teeth do the same?
|
Repost
|
explainlikeimfive
|
[
"don2i1u"
] |
[
"Contrary to semi-popular belief, teeth are not bones. As a result, they do not feature the same regenerative abilities as bones."
] |
[
5
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
l669ea
|
What is the point of all the different types of screw heads?
|
Other
|
explainlikeimfive
|
[
"gkydi8a",
"gkyepqz"
] |
[
"Sometimes there are specific needs. One might need a fastener that can be used with a large torque but a small head, where Torx-style fasteners and the like are often used. Or the manufacturer may want to make it difficult to remove the screw using a obscure or custom tool interdac."
] |
[
7
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
a60ysp
|
When doing surgery, how are surgeons able to see what they are doing? How is there not bleeding obstructing their view? I.e. surgery to remove a fibromatosis from a finger.
|
Biology
|
explainlikeimfive
|
[
"ebqtpim",
"ebqtp8b",
"ebqtpg7",
"ebqtr8h"
] |
[
"A medical student here. There is bleeding but there is a suction machine in the OTs and usually one of the junior residents/doctors is cleaning(suctioning) up the blood as soon as there is some. They can also flush the site with sterile water and then suction it to clean it up even more. And then there is a bright light right on top of the surgical site so they're able to see everything pretty clearly."
] |
[
7
] |
[
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
7ljjd0
|
How does a whetstone sharpen a blade?
|
Engineering
|
explainlikeimfive
|
[
"drmomxn"
] |
[
"By scraping off the metal that's sticking out above a flat plane. By using two flat planes on either side of a blade you can form a sharp edge where the planes intersect."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
dwrfcd
|
Why are economists so sure that there’s a recession looming ahead?
|
Economics
|
explainlikeimfive
|
[
"f7kx5g4",
"f7kxg9q"
] |
[
"Recessions normally happen every 10-15 years or so, so its quite likely it'll happen soon. Also there are several indicators that tend to go bad before the recession hits, many of which are firing. There is also poor policy, we expect the trade war or Brexit to cause a recession, so it makes sense to expect one soon. Also some countries are already in a recession, so that might spread outward."
] |
[
4
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
iqnq2h
|
why do bubbles in champagne rise up in a straight line originating from one point?
|
Physics
|
explainlikeimfive
|
[
"g4t6gvk",
"g4t9dp4"
] |
[
"They are a lower density than the liquid around them, so they rise against gravity, which basically means straight up. They form around nucleation points, tiny particles of dirt or scratches in the glass."
] |
[
12
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
ffaysg
|
How was the geographic South Pole first reached?
|
Compasses are pretty useless at the Poles, so how did they find it?
|
Other
|
explainlikeimfive
|
[
"fjxasgs"
] |
[
"The geographic poles and the magnetic poles are very far apart from each other. So a compass will work reasonably well near the geographic south pole but will point towards the magnetic south pole. However it is still not as accurate as closer to the equator because the magnetic field lines does not always point directly to the magnetic poles. The Norwegian expedition that reached the South Pole first used techniques developed for ship navigation. The daily navigation were done by dead reckoning, basically go in a straight line and count on the odometer how far you have gone. They either used the compass for this or they used land features like mountains and rocks or even the position of the Sun. But for more accurate navigation throughout the trip they used astronomical observations. Depending on where you are on the globe the position of the stars, Sun, Moon and planets will be different. By measuring the position of these accurately they were able to locate their position with very high accuracy. At the South Pole they spent days making these observations to make sure they were in the correct position. This also involved making small excursions in four directions to make observations that indicated what hemisphere they were in."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
7p650d
|
Why do most cameras have a lower limit for ISO that is ISO100?
|
I know some cameras have limits that are lower like ISO50, but why is there a lower limit to ISO in the first place, as it's just an amplification of the electric signal coming from the sensor?
|
Technology
|
explainlikeimfive
|
[
"dseyxw9"
] |
[
"The signal coming off the sensor has a certain noise figure. The ISO setting adjusts how much this signal is amplified before being digitised but there's a limit in the range of this amplification. If you allowed, a minimum setting of say, ISO50 instead of ISO100, that would increase the amount of noise being digitised at any given high ISO setting. It's more important to maximise high ISO performance since you can always achieve the same effect as low ISO with ND filters."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
anp9pb
|
How do light and heat always come together
|
I was thinking about this yesterday and I want to know why light always ends up getting warm/hot and why if something is hot enough it always ends up giving off light. What's the relationship between light and heat?
|
Physics
|
explainlikeimfive
|
[
"efv0i5h"
] |
[
"Heat is merely light at a longer wavelength than we can see. In other words it's just another form of electromagnetic wave. The visible light spectrum runs from red to violet. Heat is just outside this range at the red end, hence we call it _infrared_ radiation. Things like sunlight have a wide spectrum of electromagnetic radiation from the infrared (which we feel as heat) through to ultra violet (beyond the violet end of the scale). So when we sit in the sun we are not only illuminated by it but also warmed by it, and the UV can burn our skin if we're not careful. Hot objects glow because the electrons in their atoms become more 'excited' the hotter they get. This makes them flip between higher and lower energy states, and sometimes dropping to a lower energy state means the electron emits a photon to get rid of the energy. It's these photons we see as a glow."
] |
[
9
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
cgb7hf
|
What makes a helicopter go forward? I know the main rotor generates lift and the side facing one on the tail keeps it from spinning out, but what allows it to move forward/tilt different directions?
|
Engineering
|
explainlikeimfive
|
[
"eufsync",
"euftdz5"
] |
[
"The angle of the blades of the main rotor can change mid-revolution, so that they can be more flat at the front, and at a higher angle at the back, creating more lift in the back and tilting the entire helicopter forward. Helicopter pilots also have another control available to them: the collective, which changes the average pitch of the rotors, allowing them to control lift."
] |
[
8
] |
[
[],
[
"https://i.imgur.com/vYYQud0.jpg",
"https://www.youtube.com/watch?v=Pu48f7s5Ru8"
]
] |
[
"url"
] |
[
"url"
] |
|
e0iudj
|
Headaches related to dehydration.
|
When dehydrated for a few days or weeks I have no headaches or dry mouth feeling. As soon as I start hydrating again I get a headache within hours and my mouth suddenly feels ultra dry. Why?
|
Biology
|
explainlikeimfive
|
[
"f8egw0u",
"f8eg392"
] |
[
"Dude you shouldn't be \"dehydrated for a few days or weeks\". Drink water at every opportunity. You'll be much better for it."
] |
[
6
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
labay4
|
How do fish swim? How does the side to side motion propel them forward?
|
Biology
|
explainlikeimfive
|
[
"glmy6o4"
] |
[
"The angle of their fins, mostly their tail, pushes water backwards. There's also some sideways motion but it's mostly pushing water backwards, which pushes the fish forwards."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
7vj5g7
|
How do audio cassette tapes play different tracks depending on Side A or Side B?
|
Technology
|
explainlikeimfive
|
[
"dtsoy7j"
] |
[
"Take two strips of paper. One one write banana. On th eother write orange. Rotate the strip with orange 180 degrees and put it directly under banana. Like this: banana ǝƃuɐɹo This is how it works but with magnetic tape, the old read heads only read the one half. Flipping tape reversed what side would be read. Newer decks just reversed direction and change position of the read head."
] |
[
8
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
6w4sme
|
how come we never remember falling asleep?
|
Repost
|
explainlikeimfive
|
[
"dm5c8uw"
] |
[
"Exactly this is know as Sleep-related retrograde amnesia and here is a simple explanation: > The occurence of sleep appears to close the gate between short-term memory and long-term memory. All information in short-term memory storage at the onset of sleep apparently fades away. Accordingly, although one is unequivocally aware of the environment (perceiving) before falling asleep, these perceptions are usually lost from memory because they are not transferred into more permanent memory storage. > [Source]( URL_0 )"
] |
[
7
] |
[
[
"https://www.amazon.com/Stanford-Sleep-Book-William-Dement/dp/1495119467"
]
] |
[
"url"
] |
[
"url"
] |
|
cat883
|
Why does the air in a stuffy room literally feel thicker?
|
Biology
|
explainlikeimfive
|
[
"etaxlpu"
] |
[
"Stuffiness is usually associated with elevated humidity levels. In these cases, the air is actually heavier as humid air contains more water vapor. It is worth noting that as air temperature increases, it can hold more water vapor, which increases the stuffiness effect. For additional information on the properties of air, try googling info on the psychrometric chart. The topics can get advanced in a hurry, but could be informative."
] |
[
5
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
6oyr98
|
Most of the symptoms you hear of from cancer patients are actually symptoms of the treatments they are going through. So what are the actual symptoms of cancer and how does cancer destroy the human body?
|
Repost
|
explainlikeimfive
|
[
"dkld035"
] |
[
"This is a tough question because there are hundreds of known cancers, and theoretically infinite unknown cancers. Each is as different as one species of bird is different from another species of bird. That is to say they share some characteristics, but individual types of cancers can have distict attributes as well as individual cases of each cancer can have subtle differences. The main connection of all cancers is that they are cells which no longer respect the rules and requests of the host organism. They are rogue cells. Almost a different entity forming inside the host. Since they don't play by the rules, they can wreak havok on those around them. When some bad cancer cells move into town you could say the neighborhood goes to shit. If it's bowl cancer you may lose the ability to handle waste, killing you from we toxicity. If it's stomach cancer you may become unable to eat or digest food. Starving you to death. Cancer also had a tendency to stop respecting it's original role also. Stomach cancer cells may make it into your blood stream, land in your heart, and just stay growing there. They don't care. It's warm and there is food. Kind of like homeless people setting up a camp in the downtown. They steal bikes, shit everywhere, and drop their needless wherever they want. Eventually killing the area around them. Meanwhile, your body sometimes recognized them as a post and attached then, other times it see them as regular citizens and continues protecting them. Hope that helps."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
5vpqtn
|
If light doesn't move through time, why does light take time to go anywhere?
|
From my understanding of it, light travels at light speed, the speed traveling through space at which it stops traveling into the future. If light doesn't travel into the future, then wouldn't that mean that it would reach a location at the same time that it started somewhere else? Shouldn't it take 0 time for light to reach a new location, meaning its speed is infinite?
|
Physics
|
explainlikeimfive
|
[
"de3x3fh",
"de3u3dg",
"de3ud7j",
"de4leuz",
"de3x26d"
] |
[
"To tackle this question, let's assume that light isn't the universal speed limit. (The speed limit being infinite). #We Know: It takes an exponentially increasing amount of energy to accelerate an object of mass x. Think of this as a 100m long ramp that grows steeper (as a function of mass) until it's completely vertical. **Ramp of Heavy Mass:** > & nbsp; & nbsp; & nbsp; & nbsp;| > & nbsp; & nbsp; & nbsp; & nbsp;| > _/ **Ramp of Small Mass:** > & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp;| > & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp;/ > & nbsp;__/ **Ramp of No Mass:** > & nbsp;__________ #We Conclude: 1. We can travel fastest on the ramp that is level rather than one that's uphill. 2. It is impossible to travel faster than the level ramp allows as negative mass and thus a negative declination cannot exist. 3. Therefore, When we have no mass, we travel the fastest. #Tying It Together **Fun Fact:** Light has a mass of 0! Thus using the logic from above, it is the fastest any thing can move on our \"ramp.\" Let's scale it down to easier to manage numbers. The speed of light is 299,792,458 m/s. Let's Say instead that the speed of light is 100 m/s, traveling the ramp in 1 second. > From my understanding of it, light travels at light speed, the speed traveling through space at which it stops traveling into the future. ###Defining The Future: In the above scenario, on one end of the ramp I have a flashlight. You are on the other end. Light has a mass of 0, and our \"speed limit\" we defined for that mass is 100 m/s. When I turn it on, you should see the light 1 second later. For time t(seconds) from **My Perspective:** > **t(0)** - Present > & nbsp; & nbsp; & nbsp; & nbsp;I Turn on the light. It begins shining towards you, hitting you at: > **t(1)** - Future > & nbsp; & nbsp; & nbsp; & nbsp;The light hits you 100m away. **Your Perspective** > **t(0)** - Past > & nbsp; & nbsp; & nbsp; & nbsp;It's dark. No light. > **t(1)** - Present > & nbsp; & nbsp; & nbsp; & nbsp;You see my light. So our \"speed limit\" (light) caused: 1. T= 0 to be both the Present and Past simultaneously. 2. T= 1 to be both the Future and Present simultaneously. > If light doesn't travel into the future, then wouldn't that mean that it would reach a location at the same time that it started somewhere else? Shouldn't it take 0 time for light to reach a new location, meaning its speed is infinite? Simple Contradiction Proof: Assume: Light has infinite speed causing it to not travel to the future. That Means: * t(0) Present: I turn on the light. * t(0) Present: The light hits you. The fact both of our times are t = 0 contradicts the **law** we defined above saying the fastest light moves is 100 m/s. So we need another time reference point 1 second later at t = 1. That would mean we have a \"future\". TL-DR; I took a ton of adderall to study for a test and did this instead."
] |
[
161
] |
[
[],
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
haun9c
|
How is it possible to breed and manipulate fruit trees. I always see pictures like 'bananas used look like this and carrots etc' but how were we able to change them. Also to then change them throughout the world.
|
Biology
|
explainlikeimfive
|
[
"fv4xz65",
"fv4z3nx"
] |
[
"Artificial selection, for example: You are a farmer, you are cultivating tomatoes, they are fugly but 1 tree is ok, you take the seeds of that tree and plant them, kill all the other trees, you get better tomatoes, in this new generation there are some that are better, take their seeds, plant, find the best of the best, take seeds plant. That's pretty much it…"
] |
[
16
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
9go12l
|
How do sites know when you're using an ad block extension?
|
How do sites know that you're using an ad-blocker, and could they use the same process to show you an ad in a similar way to how ask you to shut the ad-block off in the pop-up?
|
Technology
|
explainlikeimfive
|
[
"e65jmbl",
"e65jmi8"
] |
[
"They typically do it by using an algorithm that baits the adblocker into blocking a honeypot and checking if the honeypot is still there. When the webpage loads, it loads a script that is blocked by the adblocker, then another script is loaded to check if the script is still there - if it's not it displays a message"
] |
[
6
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
hhclgw
|
what's the difference between tomato paste, tomato sauce and tomato purée ?
|
Other
|
explainlikeimfive
|
[
"fw98rld"
] |
[
"Consistency / thickness and use and what someone means might differ based on where they live. Tomato sauce is usually hot and ready to eat. If the person saying it is from the UK, they might mean ketchup from a bottle. Tomato paste is very thick. It's used to add flavour and thicken things, usually you fry it in your other ingredients before adding liquid. 'Tomato paste' is what Americans usually call this. Tomato puree *really* depends on where you live. In the UK, that's usually what people call tomato paste, the very thick stuff. In the US, 'puree' usually means a slightly thick ingredient, like crushed or blended tomatoes that you can pour. In the UK, people generally call this 'tomato passata'."
] |
[
5
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
eyb0le
|
How does a Wi-Fi extender work? Let's say if a certain location has a signal of -50dBm, how does adding an extender at that exact location boost the signal around it?
|
Technology
|
explainlikeimfive
|
[
"fgg3i47",
"fgg4yvx",
"fggasik",
"fgg6cob"
] |
[
"You add it before the signal drops, then it repeats the signal so it can be accessed further away."
] |
[
9
] |
[
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
e0gwx3
|
which is the preferred method to address under arm sweating? Deodorants or anti-perspirants? I’ve heard anti-perspirants are possibly dangerous for you to use long term (carcinogenic?)...
|
Other
|
explainlikeimfive
|
[
"f8dw3xe",
"f8dznks",
"f8dumji",
"f8dxf81"
] |
[
"Antiperspirants are not carcinogenic. That's a dumb conspiracy theory on the same level as vaccines causing autism or cell phones give you brain cancer. Billions of people world wide use antiperspirant every day and have done so for decades. If it were dangerous in any way, you'd know it."
] |
[
10
] |
[
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
96e8rj
|
Why can we move our 70-80kg body around easily, but carrying just about 10kg will make us noticeably slower and drain stamina faster?
|
Biology
|
explainlikeimfive
|
[
"e3zucf0"
] |
[
"Our bodies are made to withstand that weight, our articulations, muscles, tendons, and nervous system work together to allow us to not just withstand the weight, but also be able to jump and run alongside other things. Articulations aren't so simple as they may seem, they are formed in specialized ways in order to maximize the weight they can handle and the movements they can allow. The same goes for muscles and bones. Also, iirc, most of the body weight is supported by the legs and feet, which, again, are especially well suited for doing so. When you carry something that isn't your body, your energy consumption isn't as optimal since your body isn't made for that specific task."
] |
[
6
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
nsyeb2
|
My headphones "broke" and now I don't hear lead vocals anymore and the sound quality is really bad - Why?
|
This is the 4th time any of my headphones "break" like this. It's really fascinating hearing the background vocals and...basically everything that's normally "hidden behind" the lead vocals of my favourite songs.
|
Technology
|
explainlikeimfive
|
[
"h0rkvi9"
] |
[
"Your cord / connector is fucked. It's a stereo-mixing thing - the voice is usually exactly centre, and the music is around the edges. Your ground connection has broken, so it's effectively subtracting one channel from the other - filtering out what's common, and only playing what's different. If it's possible to replace the cord, your headphones themselves should be fine. If not, make sure your next headphones use a separate cable, rather than a hardwired one. Then when this happens next time, you just go buy an aux cord. (some brands use stupid small-diameter sockets; gotta watch for that)"
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
5yyyim
|
What is the difference between TVs that are the same size and quality? For example: A 720p 32 inch led tv from Hisense manufactured in 2011 vs a 720p 32 inch led tv from Samsung manufactured in 2016.
|
Technology
|
explainlikeimfive
|
[
"detyafw",
"detz3kp",
"deuqm3r",
"deu3jjh",
"deua0n5"
] |
[
"Some parameters that might be different: * Brightness. A TV that's not bright enough will be difficult to watch in brightly lit environments, like a sunlit room. * Contrast. The difference between the brightest and darkest color the TV can display. Higher contrast means deeper blacks and brighter whites. * Color reproduction. How accurately the TV shows colors. * Transition time. The time it takes a pixel on the TV to switch colors. Too slow and fast movement will look blurry. * Input lag. How long it takes between a signal being received by the TV to actually being displayed. It's relevant if you play games on the TV, the lower the input lag the more responsive the game will feel. * Power use and reliability. * Features. A newer, fancier TV is probably going to have a lot extra features like automatic brightness control or connecting to the internet to watch YouTube or Netflix on its own without having to attach a computer. There's probably more but that's what I can think of right now."
] |
[
151
] |
[
[],
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
ak9kph
|
Why do low and extremely high frequencies require more intensity to be just barely audible as compared to the middle range of frequencies?
|
Physics
|
explainlikeimfive
|
[
"ef2t23u"
] |
[
"This is not as much a physics question as a biology question. It is how the (human presumably) ear is designed. It is similar to why our eyes can only detect colors in a limited range of frequencies. Our organs are adapted to react to the stimuli that are most useful such as detecting the presence of predator and prey. Anything else is \"wasteful\" use of mental processing ability."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
cxgyn2
|
what is it about long car journeys that makes us so tired?
|
Biology
|
explainlikeimfive
|
[
"eykyyc6",
"eylan4b",
"eyl3yj1",
"eykzzdq"
] |
[
"You’re sitting there, just staring straight ahead. It definitely makes your eyes tired. Driving is also fairly mentally active as you need to stay aware and watch out for others which is also tiring. There’s also such a thing as being hypnotized by the white lines that split the lanes."
] |
[
18
] |
[
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
86qurw
|
Grapes placed in strong sugar solution don't shrink, but when they are placed in a strong salt solution, they do shrink
|
Biology
|
explainlikeimfive
|
[
"dw76n7k",
"dw78470"
] |
[
"Water always follows salt. The water inside a grape will leave to try to balance the high salt content outside of it, so it shrivels. Assuming the sugar solution is sucrose (table sugar), you probably have a situation where the percent of sugar inside the grape is equal to the percent of sugar in the solution. Grapes have a high concentration of sugar naturally so it probably takes much more sugar than salt to see a shriveling effect in the grape."
] |
[
20
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
hdrxjk
|
How do self healing phone screen protectors work?
|
Chemistry
|
explainlikeimfive
|
[
"fvmz7uc"
] |
[
"\"Self-Healing\" is just a fancy buzz word for elasticity. What you are essentially doing when you scratch the screen protector is putting a shallow dent it in. Over time, the elasticity of the material allows the dent to return to normal."
] |
[
26
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
83g890
|
Why does it seem nearly impossible to forget how to ride a bike?
|
Biology
|
explainlikeimfive
|
[
"dvhk5zp"
] |
[
"It is called 'muscle memory' and is the strongest form of memory. Repetitive involuntary muscular actions such as swimming, walking, cycling etc are thus very hard to forget. Imagine if you could forget how to walk!"
] |
[
7
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
9qnrk2
|
Why isn't there an ad blocker which still generates revenue for websites?
|
Technology
|
explainlikeimfive
|
[
"e8agbky",
"e8ak8dl",
"e8an2rg",
"e8ascus",
"e8am8ea",
"e8als46",
"e8aoy3c",
"e8aq4b9"
] |
[
"The entire reason that ad blockers work is because ads are generally stored on *other servers* because advertisers **don't trust websites not to cheat**. Without a trusted method of serving up ads, the online advertising market is worthless. Crafty advertisers will also constantly find ways to work around any rules the ad blocker tries to implement in order to differentiate between real contact and ads."
] |
[
77
] |
[
[],
[
"https://brave.com/"
],
[],
[],
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
goxesb
|
Where do dinosaurs fit into the Christianity timeline?
|
Other
|
explainlikeimfive
|
[
"frilh5x"
] |
[
"As a Christian this is how I understand it. Also disclaimer, I’m gonna ask that people respect my personal beliefs. I know it doesn’t necessarily make sense to be religious, but I am. Remember time is relative to the observer, and this relatively is dependent on proximity to a gravitational mass. So from God’s perspective it could have very easily been 5000s years which translates to billions of years our time. So it’s kinda like playing a civ management game, but on times a trillion speed. So when he’s relaying his message to the prophets, he’s like “Brah, it’s been 5000 years” but that’s from his perspective. Now before anyone says “why didn’t God just say it from a human perspective??” I can’t figure out the motives of a celestial being, so I have no idea."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
8ccnrl
|
What is "The Axiom of Choice"?
|
I don't understand a lot of complex mathematics, this seems a bit heady to me. Can anyone help?
|
Mathematics
|
explainlikeimfive
|
[
"dxdx76g"
] |
[
"It states that, for any number of non-empty sets (sets are just groups of things, usually numbers, and non-empty just means there's at least 1 thing in that group), there's a way to choose 1 thing from every set with a single statement. For example, if you had 10 sets of numbers, no matter how many numbers are in each set or what those numbers are, you can say \"I want the highest number from each set\" and you'll get something from each set. Or if you infinite pairs of shoes, you could say \"I want every left shoe\" and you'd get a shoe from every pair. Or if you had 80 bags of random assorted objects, you could say \"I want the object made of the least amount of atoms\" and you'd get an object from each bag. The axiom of choice says that for any sets with at least one thing in them, there's some question like this you can ask. Now, when you get into complex mathematics, there can be some debate over whether or not this is actually true, mostly related to sets that contain infinite numbers, but most mathematicians agree that it is true."
] |
[
5
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
62x14t
|
How does cinemas work?
|
Culture
|
explainlikeimfive
|
[
"dfprrwz"
] |
[
"So movies nowadays are pretty much all digital. A few years ago Hollywood stopped wanting to ship any film out. They get it on an external hard drive which is delivered to the theatre a couple days before it is to premiere on the screens. They're very proprietary to they type of projector presenting it and actually to the specific projector that is to be used. So for example on Wednesday the theatre might receive the movie via a delivery then they have to \"ingest\" it into the hard drive of the projector of the screen they want to use (some may have upgraded to a centralized network so they don't have to re-ingest it every time they want to move the movie to a different screen). Once it is ingested they load it up like a playlist; ads, commercials, trailers, queues for when the lights turn on and off, it's very much like an iTunes playlist. The night before or the morning of when the movie actually premieres the theatre will receive a \"key\" that is an ecrypted password that will allow the certain projector to play the particular file (movie) that will have to be uploaded to the projector. At that point it's essentially just set to a timer for when the movie is supposed to play."
] |
[
9
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
n8urmi
|
Why can potatoes and onions continue to grow sprouts while in dry storage?
|
Biology
|
explainlikeimfive
|
[
"gxkl3hy"
] |
[
"You mean like why can they do that while most plants require soil, water, and light to sprout? It’s because the energy needed to launch a sprout was already captured and is stored in the potato/onion. Potatoes are a root vegetable and they are created as energy stores. Thus the energy needed to launch a sprout is already there."
] |
[
16
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
7ccrvz
|
Why can't a person, that has suffered from hypothermia, be revived?
|
Other
|
explainlikeimfive
|
[
"dpown5j",
"dpow7b9"
] |
[
"Defrosted? Are you talking about hypothermia or being frozen? In the case of hypothermia a person can be revived from a pretty low temperature with varying odds of success. It gets difficult the lower you go because in general the biochemical process to make your cells and organs function only work efficiently (or at all) in a pretty narrow temperature range. Once out of those range they may not all be able to start back up again. If you're talking about being frozen it's similar but even harder. The processes don't just slow to inefficiency they stop entirely including brain activity. There might be some way to systematically jump start them again, but it's well beyond any technology we currently possess. Besides that, the process of freezing a body in the first place can very easily cause a lot of the cells to rupture as the water in them expands/freezes. If that happens to many of your cells and there wouldn't be a body to revive at all, you'd have freezer-burned steak."
] |
[
4
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
hntxmd
|
Why aren't all the truck wheels on the road?
|
Im talking semi's with trailers, sometimes they dont have all the wheels on the road. Like one set is lifted up, why?
|
Engineering
|
explainlikeimfive
|
[
"fxdlcy2",
"fxdvwtz",
"fxdlda1",
"fxdr7yo"
] |
[
"It mostly has to do with weight. Fewer wheels mean less friction, less moving parts, and better mileage. However, under very heavy loads, the trucks need that additional support on the road to evenly distribute the weight."
] |
[
25
] |
[
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
n6ta40
|
How does the wind work? Where does it come from? What causes it to stop?
|
Earth Science
|
explainlikeimfive
|
[
"gx97mcm"
] |
[
"just like most of the phenomenon on earth this is also caused by sun. The sun unevenly heats the air causing a change in densities. This causes the air to move from higher density to lower density which we call wind."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
jqnlcg
|
The human brain’s storage capacity is unknown, but generally accepted to be very large. Hypothetically, what happens if the brain’s storage space is full?
|
Biology
|
explainlikeimfive
|
[
"gbo8qf2",
"gbo9tmh",
"gboaja2",
"gbobjw0",
"gbotkig",
"gbofwr3",
"gboneuk"
] |
[
"Information is saved by the formation of connections between nerve cells. When you learn something new, new connections between nerve cells are formed. Over time synapses that aren't used deteriorate and make space for new ones and the information they held is forgotten. So basically you always forget unimportant stuff you don't need anymore to be able to remember new information."
] |
[
136
] |
[
[],
[
"https://www.scientificamerican.com/article/what-is-the-memory-capacity/"
],
[],
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
6316am
|
How activated charcoal is for detoxing while charcoal can increase the risk of cancer?
|
Other
|
explainlikeimfive
|
[
"dfqko3p",
"dfqlnge"
] |
[
"Activated charcoal tends to absorb unwanted reactive stuff floating around, which is why it's used in filters. It's like a sponge. Destroying the charcoal by burning it *makes* fumes and reactive stuff. That's like grinding the sponge into dust."
] |
[
6
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
6aaw13
|
Why do you get startled/feel a rush of a adrenaline if you catch yourself falling asleep?
|
Repost
|
explainlikeimfive
|
[
"dhd3udp"
] |
[
"Are you talking about hypnic jerk (sometimes called hypnagogic jerk)? That feeling where you jerk suddenly back awake sometimes when you're falling asleep? The prevailing theory is this is an evolutionary holdover from our earlier primate days, and is a danger response so our ancestors didn't accidentally fall out of trees."
] |
[
5
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
d12z5q
|
How do actors portray dead characters in movies? Do they actually sit there and just hold their breath?
|
Other
|
explainlikeimfive
|
[
"ezgjh2z"
] |
[
"Yep. For extended/dangerous scenes (or if it’s cheaper to create one in case the actor’s per-day rate is more expensive), a highly realistic dummy is created. (See *The Autopsy of Jane Doe*, Zod’s body in *Batman v. Superman* or Kristen Stewart’s frozen body in *Zathura.*)"
] |
[
16
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
9l0hn4
|
According to Google your brain uses 20% of the oxygen you take in; what does the brain need all that O2 for? How is it being used?
|
Biology
|
explainlikeimfive
|
[
"e733hdm",
"e733mqa"
] |
[
"It needs all that O2 for metabolizing approximately 170 grams of glucose per day, to power itself. Some of the power gets used to run your conscious thoughts, some to store, retrieve, and overwrite memories, some gets spent on deriving meaning from language and determine the shape of objects, some is used for continuously predicting what sounds should come next and alert your attention system (which also uses power) when a sound is either unexpected or missing. That's barely scratching the surface of what's going on in your brain every second of every day (and most of the night, your brain runs at near 100% speed at all times except during deep sleep and if you're in a coma). It takes a lot of oxygen."
] |
[
36
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
6hqvq0
|
why are bugs attracted to light?
|
Biology
|
explainlikeimfive
|
[
"dj0geoo",
"dj0fx8r"
] |
[
"Because a close-by and bright light source confuses them. Normally, all their light comes from the sun and moon in the sky, which means, as long as they're right-side up, both eyes will get a similar amount of light. However, if there's a lightbulb or candle or something right next to them, the eye closer to the light source will be getting a disproportionate amount of light compared to the eye that's facing away. They try to orient themselves so that both eyes get about the same amount of light. This generally results in them flying straight towards the light source."
] |
[
15
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
dm2h10
|
Why are far away objects in the mirror still blurry without my glasses on?
|
Wouldn't the reflection act like a picture on the mirror?
|
Physics
|
explainlikeimfive
|
[
"f4w3lkd",
"f4w4kc5"
] |
[
"The mirror doesn't change the focal distance, it just inverts the image front-to-back. Even though the mirror is only two feet away, the light is still actually traveling considerably farther and your eyes are focusing for that total distance."
] |
[
7
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
nji8dg
|
Considering that CCTV footage is the primary way of identifying shoplifters, bank robbers, etc., why is the footage for something so important such low quality that you can barely identify a face?
|
Technology
|
explainlikeimfive
|
[
"gz7hsza",
"gz7hfdr",
"gz7i7bh"
] |
[
"CCTV cameras can't be recording all the time because high res video uses up a lot of space. So CCTVs use tricks like lower resolutions, temporary shutdowns, and compression to reduce the amount of storage they require. You CAN have super high quality CCTV footage but a lot of businesses don't bother because it's too expensive. Camera systems are often very old and outdated and ostensibly only exist to reduce the cost of insurance coverage. Casinos for example have incredible CCTV setups, while a gas station will have a couple of cheap cameras and a couple TB of NVR (video recording) Catching thieves also isn't as important as you might think. A lot of businesses don't bother with the hassle of catching petty thieves since it's easy to claim the insurance or write-off the cost than it is to pursue in court. Casinos however are very much interested in pursuing and banning cheaters. The stakes for them are much much higher. Footage shown on TV is sometimes also deliberately lowered in quality to protect intellectual property or by-standers."
] |
[
57
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
epjptz
|
Why do things that are burnt often turn black?
|
Chemistry
|
explainlikeimfive
|
[
"fejr088"
] |
[
"If you burn something organic (food, wood, plastic), then it is because a layer of amorphous carbon (soot or charcoal) is formed on a surface, due to incomplete burning of the material being burnt."
] |
[
14
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
bgpeza
|
In sci-fi movies, spaceships are shown with engines burning fuel in normal travel. Would this be necessary? I thought spacecraft reached a max speed and then coasted since there is no gravity.
|
Physics
|
explainlikeimfive
|
[
"elmm0f4",
"elmlmgs",
"elmn4oo",
"elmlogc",
"elmlnmm"
] |
[
"There is no max speed. The fastest way to get to your destination is to accelerate towards it for the first half of the trip, then flip around midway and spend the next half of the trip decelerating We don't do that with our space probes because they're fuel limited not time limited. We shoot them off on a trajectory that'll get them where we want with minimal fuel then wait the few years it takes them to coast there. If you had a rocket that could accelerate at 1 G and enough fuel to sustain it then you could travel from the Earth to Jupiter in just a week, and you'd have Earth standard gravity for the whole trip which is nice."
] |
[
19
] |
[
[],
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
fl7tf5
|
Why do higher end vehicles tend to have their car models named after numbers?
|
Other
|
explainlikeimfive
|
[
"fkx11td",
"fkx7859",
"fkxeht4",
"fkx77u3",
"fkxotwq"
] |
[
"Some car makers rely on the strength of their name while others rely on the strength of their models names. For example, people are more apt to take pride in saying they drive a Mustang or a Corvette rather than say they drive a Ford or a Chevrolet. Other companies don’t need the model name recognition - if you drive a Lexus that is enough. Lamborghini is an example of a company that uses model names like Gallardo and Murcielago but at the end of day people just recognize it as a Lambo."
] |
[
32
] |
[
[],
[],
[],
[
"https://en.wikipedia.org/wiki/Fiat_Uno",
"https://en.wikipedia.org/wiki/Fiat\\_Uno"
],
[]
] |
[
"url"
] |
[
"url"
] |
|
5xxrim
|
Would there be any noticeable negative effects if you just used regular shampoo to clean yourself compared to soap/body wash for years straight?
|
I only use Suave shampoo for my hair and body, have been for years. I've never been told I'm "smelly" or have noticed any negative skin conditions. So why do they have multiple products to use on every part of your body (besides to sell you 3 products when they can sell you 1 and lose sales)
|
Other
|
explainlikeimfive
|
[
"deloo37"
] |
[
"No negative effects. If you read the labels, almost all products have similar cleansing agents. It's all about companies making money off of hundreds of different products. I know someone who uses regular dove soap for face, head and body and has never had issues. (He's got very short/shaved hair on his head)."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
85q65s
|
How is it that the average human can store tens of thousands of words in its vocabulary, but if asked to list them all by hand it would be very difficult to name from memory even a fraction of that?
|
Biology
|
explainlikeimfive
|
[
"dvzcksq",
"dvzcryl",
"dvzex42",
"dvzcx9g",
"dvzfu2f",
"dvzgslc"
] |
[
"The way I see it is, we don’t remember just words we remember the ideas behind and relationships of the words. That makes it really hard to remember words if we aren’t thinking of the context of the words."
] |
[
533
] |
[
[],
[],
[
"http://www1.cmc.edu/pages/faculty/welliott/Shakespeare%20Vocabulary%20Chapter%20911.pdf"
],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
aroc3p
|
How does the brain change itself when you're doing meditation/CBT?
|
I've seen some articles suggesting that meditations restructured the brain. At the same time in David Burns' book "Feeling good" confirms a study that watched patients with CBT having their brain also restructure. How does it actually change itself and what kind of change is that?
|
Biology
|
explainlikeimfive
|
[
"egp795n",
"egp6x0o"
] |
[
"It is pretty complicated but at its core you are basically changing the way that neural cascades occur. Imagine you hold the belief you are undesirable. When you get invited to a party this belief will color the invitation to seem threatening because there is an automatic assumption that 'I will get hurt emotionally' and so you don't go. In therapy you access the emotion and then change the script. Increasingly there is goodnresearch showing that CBT is less effective when there is not emotional activation because people's views change (e.g. they learn their thoughts are irrational) but they still feel scared. When there is emotional activation there is more room for neural plasticity and reconsolidation. Nonetheless some hard core cognitive therapists may disagree with me here and think that changing your thoughts is enough but same difference wrt your question. CBT also involves changing how you act. This also gives a chance for new lived experiences that disconfirm old scripts and help you build new ones. The new script might be \"parties are kind of fun\" so now when you are invited out the threat system is not activated and instead the reward system turns on. Again not 1:1 but generally that's how it works. At another level by noticing your thoughts as thoughts you are using metacogntive awareness to defuse from the script and see it as a belief instead of a fact. This means that when the script is activated the prefrontal cortex can activate along with the threat system which gives room for more change. Also the human mind and body reacts to imagined stimuli in a congruous way to the actual stimuli. Think about your favorite food and imagine how it smells and tastes. You might start salivating or feeling a craving for it. Same happens when you actually smell and imagine the food. Similarly if you are having lots of self critical thoughts, thoughts about being hurt, thoughts about being rejected etc the threat system is being activated as though the bad thing was actually happening. This causes those pathways to become potentiated meaning they need a weaker stimuli to fire which increases the odds of feeling that way and on the cycle goes. When you notice your thoughts and check to see if they are accurate you can update your thinking with a balanced thought that is more true and you are now starting to potentiate a new pathway. Mindfulness meditation works by increasing metacogntive awareness and so when you have upsetting or pleasurable experiences you can notice them instead of being consumed by them. The neuropbysiology is much the same as with the CBT bit described above. Compassionate meditation stimulates the safeness/affiliation/caretaking system which both potentiates it and also helps build more repitoirs for how you self relate. Again the neuropbysiology is similar to the above. A metaphor I like is this: imagine the mind as a field of tall wild grass. For your whole life you were walking down one trail so now it is a dirt road. That makes it the easiest and most automatic path. In therapy you start building a new path but it is hard. You trip in holes you didn't know about, your ankle gets cut by thistles, you get lost etc. By walking that new path over and over it becomes a dirt trail while the old path grows over. Neurophysiologically therapy helps you pilotentiate different systems and build new connections so that when the stimulus is there you automatically go down that new path OR it is easier to go down that new path using conscious effort. This is all super simplified but the broad strokes are accurate IMO. Source: I research mechanisms of how therapy works"
] |
[
52
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
brm9ii
|
How do whiteboards keep ink fresh?
|
If you draw on a wall / table with a marker it will dry almost immediately and won't come off easily, so how do whiteboards get around that?
|
Chemistry
|
explainlikeimfive
|
[
"eoeztqj",
"eof0o63"
] |
[
"The type of ink in the dry erase markers are formulated to sit on top of a surface. Also, the whiteboard itself is non-porous (doesn't absorb), or nearly so, so the ink just sits on top without sinking in. This is why you can get some staining on old whiteboards. The coating that makes them non-porous gets worn. Fun fact, you can use dry erase markers on any non-porous flat surface, and it'll wipe off the same."
] |
[
7
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
np85og
|
How do wild animals keep from dying of infection from wounds and open cuts?
|
Biology
|
explainlikeimfive
|
[
"h03lqrv"
] |
[
"Animals have immune systems and blood that clots, stopping wounds so they will heal. This is the same as with humans. If these things don't work the animals die."
] |
[
5
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
9jsla0
|
Trans Atlantic calls in the early 1900s
|
Watching darkest hour. I dont know why I never thought of it before. How did they talk on the phone trans Atlantic back then? I know it was only for the super elite and world leaders. It just seems to me that in those early days it had to be a hardwired grid.
|
Technology
|
explainlikeimfive
|
[
"e6txlot"
] |
[
"The earliest transatlantic cable was completed in 1858. So yes, it was a hardwired connection. But guess what? It still is! The vast majority of communication still occurs over landlines so you calls today go over such cables."
] |
[
12
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
7tivls
|
What is the difference between Mania and Psychosis?
|
Biology
|
explainlikeimfive
|
[
"dtcuaiz"
] |
[
"Psychosis often involves paranoia and delusions- usually focused around belief systems (most common I see in my life of work are people focused on the government and/or religion. With psychosis people can experience auditory, visual and tactile hallucinations. With mania you typically see impulsive and irrational behaviors, as well as feeling euphoric. With mania people are often over confident and have racing thoughts- not sleeping, high energy and not being able to slow yourself down."
] |
[
6
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
epxq93
|
How do a million people each having $1000 in savings and one person having $1000000000 differ in terms of their impact on the economy if the money is still in the same economy?
|
Economics
|
explainlikeimfive
|
[
"femdnv6",
"femdu6o"
] |
[
"Let's say they all go out for a bite to eat. Everyone orders the same thing, a 2$ hamburger. One scenario puts $2 million back into the economy, the other puts $2. Having wealth spread out gives it more chances to be spent and more impact on the economy. Sure, one person may make large purchases, but by and large you'll see more money filter in to the community with more people having money."
] |
[
41
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
8obte3
|
Why does it hurt when water goes up your nose?
|
Biology
|
explainlikeimfive
|
[
"e025p6s",
"e02hv5k"
] |
[
"So you don't die. Water doesn't go there, and when it does, you can be at risk of drowning. Having a severe reaction to even a little water up your nose it a good way to keep you out of trouble."
] |
[
8
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
9vl677
|
Why are some roads or highways concrete and some asphalt?
|
Engineering
|
explainlikeimfive
|
[
"e9d2gqq"
] |
[
"It depends on volume the roadway is expected to handle, size, scope and cost of the project, availability of resources, service life expectancy of the road, climate, complication of shutting down an existing freeway for maintenance or complete replacement, how the road authority cares for the road, just to name a few. I work for an asphalt and aggregate company, I prefer concrete because it has a much longer service life but the cost is far greater than asphalt. I drive on a road everyday my company laid the concrete for in the 1960’s and it is still in service in Minnesota where the salt and freeze/thaw cycle is very hard on any road surface."
] |
[
18
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
jn7b4v
|
How does ADHD affect ones ability to read?
|
Biology
|
explainlikeimfive
|
[
"gazn96z"
] |
[
"I get bored; easily distracted and my mind wonders easily as I struggle to engage in the content. (Adhd-I) Someone will be able to give more in depth reason but this is what happens to me. First time I was medicated I read my first book I. About three years."
] |
[
6
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
5qhf3k
|
People when they get old seem to be shorter than when they were young with at least a few inches. Why??
|
Biology
|
explainlikeimfive
|
[
"dcz9gv4"
] |
[
"Besides older people who 'stoop' or are unable to stand up completely straight due to arthritis and the such, the cervical discs in between each vertebrae get compressed as people get older. Each disc gets a little smaller, but with like 16 discs, even 1/16th of an inch per disc will shrink you by an inch.."
] |
[
10
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
8qmqtm
|
had a shower thought...why do the drawings you put in fogged glass stay there even after a session of defogging and into the reformed glass?
|
Chemistry
|
explainlikeimfive
|
[
"e0kdmz8"
] |
[
"The oils on your finger stick to the glass and less water vapor will stick to the oily sections of the glass when you re-fog it."
] |
[
8
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
hfj9dx
|
What is that “nice feeling” when you (safely) put a q-tip in your ear?
|
Biology
|
explainlikeimfive
|
[
"fvxy7yi"
] |
[
"You're stimulating your vagus nerve. Here's a previous thread about it URL_0"
] |
[
3
] |
[
[
"https://www.reddit.com/r/explainlikeimfive/comments/2stffo/eli5_the_nerve_cluster_that_is_reachable_via_qtip/"
]
] |
[
"url"
] |
[
"url"
] |
|
lh7okc
|
How does night vision work on animals and how does it compare to night vision googles?
|
Biology
|
explainlikeimfive
|
[
"gmvo7ck",
"gmvskvu"
] |
[
"Many animals that can see well at night do so by simply having eyes that are better at capturing the same light we use to see during the day. They have more and better receptors and lenses that focus more diffuse light. Night vision goggles, by contrast, work by seeing light that has a lower frequency than the light we use to see during the day. Light at this frequency is given off by basically all living things as they transfer the heat they generate to their surroundings. Even if the sun isn't around, plenty of this light gets emitted by anything decently warm in the area which night vision goggles pick up. Some animals can see this light, too, though."
] |
[
8
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
730klt
|
Why do your eyelids get puffy after crying?
|
Biology
|
explainlikeimfive
|
[
"dnmrvrx",
"dnnjy8n"
] |
[
"There are a number of factors. Tears from strong emotions are less salty than regular tears which keep your eyeball moist. Since your eyelids are \"more salty\" than the tears, the water from your tears goes into your eyelid tissue to balance out the amount of salt, causing the eyelid to swell. You could also say that blood vessels around the eyelid have to expand in order to be able to deliver that much fluid for waterworks. Also, rubbing your eyes can cause it to swell, as the friction can cause irritation of the membranes around your eyes (conjunctiva)."
] |
[
171
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
68mpd1
|
Despite having similar vocal cords, why do humans have a far versatile vocal ability than other mammals?
|
Biology
|
explainlikeimfive
|
[
"dgzs35a"
] |
[
"our vocal cords aren't actually that similar. They're built the same way but developed farther than other animals. if you gave a chimpanzee super intelligence, they still wouldn't be able to vocalize like we can. a lot of our nuance, like writing, speaking, art, comes down to our concentration of fast-twitch muscles as opposed to brute strength muscles. These fast-twitch muscles make very tiny movements, quickly, and with reliable motions, we have them all over but mostly in our hands and our lips and faces. With these, we can speak, and can write, both very intricate movements. Our vocal cords also have these. What we gave up for this, is that many of us will never be as physically strong as any other ape. The strongest of us humans is a tuesday for a bonobo. I mean, look at how thin we are in comparison, our muscle mass is not that much naturally. But, we can write and speak, and I like to think that those are more powerful things than just being really strong."
] |
[
4
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
curn6r
|
Does excessive porn consumption affect the brain negatively?
|
Biology
|
explainlikeimfive
|
[
"exxta59",
"exy5ygv"
] |
[
"you're five, you shouldn't be watching porn. But also that's a complicated question. Define \"affecting the brain negatively\". It doesn't result in lower IQ, or brain damage. But as with anything that involves dopamine, your brain will eventually require more of it (or a more extreme version of it) to feel as satisfied. Is that negatively affecting the brain? What about the way it changes someone socially? An extreme example is Ted Bundy, who claims an early addiction to porn led him to killing escorts. Or he was fucked up from the start and porn was just one of many possible catalysts. Ask a vague question, get a vague answer."
] |
[
15
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
6u7k64
|
How are some people able to understand complex mathematical problems so easily while others have to struggle?
|
Other
|
explainlikeimfive
|
[
"dlqow4z"
] |
[
"The human brain really likes patterns. One of the most important skills dealing with math is recognizing a pattern that a problem falls into and using that pattern to develop the solution. Those people for whom math seems \"easier\" have more developed mental representations of math patterns. Developing those patterns takes lots of effort but once you have them it makes dealing with individual problems much easier since you can match a pattern to a generic solution and then essentially plug in the details and get the answer. This is similar to how a car mechanic can figured out what wrong with your car much faster than you or I could or how a doctor could notice a subtle difference in symptoms that leads to the correct diagnosis and treatment when everything just looks like a cold to you or I. This is actually what the \"controversial\" common core style of doing math is really about. It's teaching students a way to analyze math problems to look for patterns. It might seem silly for smaller \"easy\" math problems but it's a huge help as the problems become more complex. Studies have shown that the kids who are \"good at math\" tend to learn this method on their own at some point in their school careers. The goal of teaching this method as part of common core is to make every kid \"good at math\" even if they lack the motivation to discover the concepts of that method on their own."
] |
[
15
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
egkfs8
|
what are intrusive thoughts and how to stop them
|
Psychology
|
explainlikeimfive
|
[
"fc76sua",
"fc7l7nv"
] |
[
"Intrusive thoughts are (mostly unwanted or harmful) thoughts that are difficult to rid yourself of. They are often triggers for an an illness or disorder. Such as a depressive not being able to stop thinking of ways to kill themselves or a person with tourettes not being able to stop thinking of a word. There are a variety of therapeutic and other techniques to get rid of the them or prevent them and not all work dpfor everyone. I suggest doing your own research for yourself or seeing a doctor to learn what works for you. Some basic ones are breathing exercises (in through the nose and out through the mouth is a traditional exercise). These are by far the most common. Note that for nearly all breathing exercises they are expecting you to be doing a full (or singer's breath). A full breath is a breath from the stomach not the chest. Singers do this as doing the latter can cause damage. Thinking of your stomach like a balloon helps some people. A good tell is if your chest and/or shoulders move, it's not correct. Meditative and yoga like exercises help some (going to to a happy place for example). The in through the nose and out through the mouth breaths actually stem from yoga. Medication helps some people with these as well. There are a variety of methods, but the issue with most of of these is that most of the solutions are preventative.which is why breathing methods are so commonly thought as they do both To explain further; There are two main schools of psychology; behavioral and psychoanalytic. Both believe in something called nature vs. Nuture, or, how much of a problem stems from environment and history (nuture) vs how much of a problem stems from biological traits (nature). Behavioral psychology generally attributes issues (and thus intrusive thoughts) to be mostly caused by behavior or environment. For behavioral theorists you can limit intrusive thoughts by changing how you act (or react) or what is around you. For example, smiling and wearing brighter colors might make you feel less depressed or dealing with tackling over reactions to certain situations Psychoanalytic theories attribute problems mostly to cognition or the way you receive (subconsciously or not) a situation or issue. They attempt to tackle problems by finding the root cause of why you feel the way you do and attempt to change the way you are thinking or precieving a situation. Both of these fields have many different techniques to deal with things"
] |
[
12
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
hm8q3h
|
What is projection in the social context and why is it bad?
|
I've heard people say stuff like "they're projecting themselves onto her" or something like that, what does it mean?
|
Other
|
explainlikeimfive
|
[
"fx3pg5b",
"fx3plaf",
"fx3v8er"
] |
[
"If you are explaining someone actions by pretending you are her, and using your value system to simulate her decisions, you are projecting yourself (your value system in this example) onto her. This is wrong, because people are not all the same. It not only gives the wrong answer, inaccurately predicting what she will do or say, and it gives the impression that you can read her mind or control her thoughts, not at all how it works."
] |
[
4
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
5twtdy
|
How does Germany and Japan handle atrocities of WW2 like concentration camps and Unit 731 in their history books?
|
Culture
|
explainlikeimfive
|
[
"ddps1m3",
"ddq2js5",
"ddpm2st",
"ddq3tyn",
"ddq3fqz",
"ddq78g8",
"ddqb3mr"
] |
[
"German history books vary from state to state (we have 16 states), but the condemnation of Nazi crimes is universal. It is also a crime in Germany to display the Nazi salute (\"Displaying symbols of anti-constitutional organisations\" - anti-constitutional in this context meaning: seeking to abolish democracy) or to incite hatred of ethnic groups. When I was in school, we took a trip to a nearby concentration camp and our class went to see Schindler's List, which was in the cinemas at that time. Various state constitutions exhort German teachers to always promote the two ideals of democracy and understanding between peoples (Völkerverständigung). There is no skirting around what happened, no apologies à la \"but the Nazis were in a bind\", no normalisation of the actions of the 3rd Reich - the books take the line that those actions and ideas were objectively evil, and that no excuse or explanation can justify them. One thing is the fate of the [expellees]( URL_0 ) from the Sudetenland and the former German territories in Poland. They were a significant voter block (nowadays, you don't hear so much about them because the first generation, which pined for their old homeland, has died off) and understandably upset at what happened to them; unfortunately (to my mind), history books sometimes seek to equate their deportation with that of the Jews. Personally, I think that that was simply to be expected when the dust settled after WW2, in contrast to what happened to the Jews, but it's an interesting example of how history books will always reflect the political stances of the author or those who commission the book (in this case, a state government that wanted to pamper the hurt feelings of the expellees). As for history books that are not school books, any serious academic German history book might analyse this or that aspect of Nazi rule slightly differently, but the consensus is that the end of Nazi rule was a good thing. Though even on May 8, 1985 (the 40th anniversary of the end of WW2 in Europe) then-President Richard von Weizsäcker made headlines with his speech (\"the 8th of May *was* a day of liberation\") because at that time many people were still alive who told themselves that they had only fought for their country and not the regime. The real difficulty in Germany always lay in people's perception of their individual guilt or non-guilt; the evilness of the 3rd Reich itself was \"officially\" never disputed in my lifetime (the 1950s is a different story), and anyone publicy doubting that quickly got into very hot water. Edit: There is an inscription on a wall of the Munich town hall: \"To the members of the US Armed Forces who on the 30th of April 1945 liberated Munich from the national socialist rule of terror.\" There are some objections to this \"cult of national shame\"; this week, a politician who voiced that view in a speech has been expelled from his right-wing populist party because the populists *do not* want to associate their brand with the Nazis (even if, in my opinion, they may privately have similar ideas)."
] |
[
61
] |
[
[
"https://en.wikipedia.org/wiki/Expulsion_of_Germans_from_Czechoslovakia"
],
[],
[],
[],
[],
[
"https://en.wikipedia.org/wiki/White_Rose",
"https://en.wikipedia.org/wiki/Inner_emigration"
],
[]
] |
[
"url"
] |
[
"url"
] |
|
axlmmu
|
If opposite magnetic poles attract (North to south) how come the north part of a compass points towards north?
|
Physics
|
explainlikeimfive
|
[
"ehu9ysl"
] |
[
"The \"north\" pointer on your compass is a south magnetic pole. It's labeled \"north\" because that's the direction it points."
] |
[
14
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
mlfgyv
|
;What’s the detriment to “highly processed” foods?
|
Other
|
explainlikeimfive
|
[
"gtl3l6i"
] |
[
"\\*In general\\*, the more you process foods the more additives get in there...salt, sugar, dyes, artificial flavours, etc. You also tend to lose water, fiber, and bacteria (depending on the food), which don't show as nutrients but can still be good for you. None of those additives are necessarily bad on their own but the more you process the farther the food's nutriotional (and non-nutritional) profile drifts from where is started. That's \\*not\\* generally true for food oil. Most of them are just squeezed out of the source plant, through a filter, and into a bottle. I'm not aware of any meaningful processing difference between, say, canola and olive oil. Hydrogenated oils (e.g. Crisco or margerine) are a different case, but just straight veggie oils? Oil is oil is oil, from a processing standpoint. There's other reasons you might like olive (it's relatively high in unsaturated fats, which can be \"good\") but that's nothing to do with processing."
] |
[
5
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
mg7l1h
|
How are metal forges made if you need to forge the metal they're made of?
|
Or rather how can equipment that's made to work with very high melting temperature metals be possible to make? And if there is some non metal material that is used for forging high temp melting point metals, why not just use it for everything?
|
Technology
|
explainlikeimfive
|
[
"gsrmyqm",
"gssobk2",
"gsrmw8o",
"gsrpkez",
"gss73v9"
] |
[
"In simplest form, early forges were made of dirt and mud. So over time (copper age, bronze age, iron age) more complicated materials could be forged and forges were improved. I guess you could compare it to cooking, fire on the ground and now ovens in homes. You can still cook over an open fire and you can still forge with a dirt forge, but there are better ways."
] |
[
8
] |
[
[],
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
70utqu
|
Why do all sign language interpreters make silly faces when they sign?
|
Are the faces apart of the language, or is it just kind of a natural human expression that people that can hear do as a compensation due to not being able to verbally communicate while they sign?
|
Culture
|
explainlikeimfive
|
[
"dn600lo",
"dn67tii",
"dn6x5c2",
"dn5zy40",
"dn626ws"
] |
[
"Facial expressions are not *essential* to most sign languages, but they are an important part of smooth communication in sign language. All of the nuance usually carried by tone of voice is expressed in facial expressions, instead. Because signs for different words can be similar, the proper expression also help provide a context that avoids confusion. For example, in American Sign Language, there is one sign for \"help\" and you use directions to indicate whether you are asking for help, offering help, or asking for/offering help about a third person. The right facial expression makes the difference between asking and offering help obvious."
] |
[
27
] |
[
[],
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
o23p97
|
Why do we usually get mental blocked when being asked on the spot?
|
Other
|
explainlikeimfive
|
[
"h249pf4",
"h25zese",
"h24i7wi"
] |
[
"If by ‘on the spot’ you mean that a person asks a question abruptly, instead of in a natural flow of conversation, probably because your brain is processing possible ulterior motives."
] |
[
15
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
5zegyw
|
What's the minimum number of people that need to survive so that when they reproduce, it doesn't become an inbred gene pool?
|
Repost
|
explainlikeimfive
|
[
"dexfm6y",
"dexfzvo",
"dexg16b",
"dexsqa6"
] |
[
"This is called the [Minimum Viable Population]( URL_0 ) According to [NewScientist]( URL_1 ) it's been calculated to 160 (unrelated) people for a space trip of 200 years, but there's no hard number for humans."
] |
[
19
] |
[
[
"https://en.wikipedia.org/wiki/Minimum_viable_population",
"https://www.newscientist.com/article/dn1936-magic-number-for-space-pioneers-calculated#.VBiC_XtDLwo"
],
[],
[
"https://www.newscientist.com/article/dn1936-magic-number-for-space-pioneers-calculated#.VBiC_XtDLwo"
],
[]
] |
[
"url"
] |
[
"url"
] |
|
j0lufa
|
why is it that when a mirror is broken, the reflection splits in to two even though it is in the same position and angle as the original one which gives only 1 reflection
|
Physics
|
explainlikeimfive
|
[
"g6snphh"
] |
[
"Instantaneously as the mirror splits, the two halves shift - ever so slightly - changing the angle. This means that they're not quite in exactly the same position or angle they were before the break. This often creates a double image, particularly if the mirror's middle broke \"inward\", causing a depression in the middle of the mirror (like from an external impact to the surface of the mirror). A different set of images could form if the mirror were broken from the back or dropped on the floor, as the fragments would angle differently on breaking"
] |
[
8
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
hna3q0
|
How do online petitions work? I’ve seen a lot of online petitions and even signed a few that I relate with but always wonder what happens after I sign it and they get the number of signatures they needs.
|
Other
|
explainlikeimfive
|
[
"fxa5yqj",
"fxb1y5o"
] |
[
"They’re usually used as a sort of proof of concept for an idea or a proposal. For example if a politician wants to build a new library in his city just saying “let’s build a new library it’ll probably be good” doesn’t go a long way, but if you can pull up a petition for a new library that 100k people signed, the proposal suddenly becomes a lot more convincing"
] |
[
3
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
9845i4
|
In a skull and crossbones, which bones are they supposed to be, if any?
|
Culture
|
explainlikeimfive
|
[
"e4d7iy2",
"e4d67k6"
] |
[
"The skull and crossbones was not originally a warning of poison or impending doom. It was a Christian emblem, like the cross or the fish. You can often find old crucifixes with a [skull and crossbones at the bottom]( URL_0 ). The bones represent the grave of Adam and the skull represents Golgotha (\"the Place of the Skulls\"), where Christ was crucified. Early Christians believed that was the same place -- Adam was buried at Golgotha and Jesus was crucified there. > Tradition has it that in this city, nay, more, on this very spot, Adam lived and died. The place where our Lord was crucified is called Calvary, because the skull of the primitive man was buried there. So it came to pass that the second Adam, that is the blood of Christ, as it dropped from the cross, washed away the sins of the buried protoplast, the first Adam, and thus the words of the apostle were fulfilled: *Awake, you that sleep, and arise from the dead, and Christ shall give you light.* -- [St. Jerome]( URL_1 ) (386 A.D.) So the skull and crossbones represented the full arc of Christianity -- from Adam to Golgotha. Adam, the first sinner, died there; Jesus, who redeemed all sinners, also died there, and washed away those sins."
] |
[
18
] |
[
[
"https://www.listia.com/auction/14413827-antique-pectoral-catholic-cross-crucifix",
"http://www.newadvent.org/fathers/3001046.htm"
],
[]
] |
[
"url"
] |
[
"url"
] |
|
bsl0hw
|
if I place both waters into a bucket from where the two oceans meet but don’t mix, why do they mix just fine in the bucket?
|
Chemistry
|
explainlikeimfive
|
[
"eoo2j06"
] |
[
"The idea of \"two oceans meet but don't mix\" is more or less a myth. Most of the pictures of this you see on the Internet are at rivermouths or headlands, where a sharp contrast between water types is visible ... but it mixes away pretty quickly. Tom Scott did a video on this recently. URL_0"
] |
[
12
] |
[
[
"https://www.youtube.com/watch?v=a4N4yQB_B4c"
]
] |
[
"url"
] |
[
"url"
] |
|
88i1wg
|
When a computer game is loading, what’s actually happening?
|
Technology
|
explainlikeimfive
|
[
"dwkqvc1",
"dwkubdl"
] |
[
"So, computer hard drives and game discs are great for storing lots of data for a long time, but it takes a little while for the device to get the information it needs, especially if other programs are busy with it. If you wanted to spawn a monster in a game, you'd have a hiccup as the game stops everything to go to the hard drive or game disc and create the monster based on the data. And these hiccups would happen every time the game needs to spawn a new monster. To make sure games are always running fast, computers and consoles have RAM. It's stick-shaped piece of hardware with lots of free space, where we can store information that we need to access multiple times, as quickly as possible. So what the game will do is, before starting a level, take all the information it knows it will need for the upcoming level (the types of monsters in it, what the textures are, the music that loops during play, etc.) and copy it from this slower storage space to a much faster one (RAM). That way your game can run stuff and create as many copies of something as it likes without any drop in performance, and your hard drive or game disc is freed up for other uses."
] |
[
41
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
6npukf
|
How do scientists know that the Sun is made of 90% Hydrogen?
|
Chemistry
|
explainlikeimfive
|
[
"dkbg941",
"dkbpwdm"
] |
[
"There might be another way as well, but one of the ways is definitely through spectral lines. URL_0 Basically, light generated by different materials don't look the same when spread by a prism. White light is a mix of the \"Primary colors\" of light Blue, red, and green and each material has a distinctive spread and mix of the colors when spread by a prism. So if you get a prism to spread light from the sun, you'd get a spread very similar to the spread created by light from Hydrogen, though of course, there would be other lines mixed in that represent the rest of the composition"
] |
[
8
] |
[
[
"https://en.wikipedia.org/wiki/Spectral_line"
],
[
"https://en.wikipedia.org/wiki/Solar_core#Composition"
]
] |
[
"url"
] |
[
"url"
] |
|
8bab6x
|
What is the biology behind being a light sleeper vs a heavy sleeper?
|
Biology
|
explainlikeimfive
|
[
"dx5fd46",
"dx5sjfy",
"dx5qj20",
"dx5zwv6",
"dx5pqeb",
"dx5yh1l",
"dx5ws69",
"dx5zf1m",
"dx66cll",
"dx5xojf",
"dx6dx6b"
] |
[
"Very little. There are all sorts of studies where people in sleep studies claim terrible or awesome sleep, yet their sleep data is very similar. Much of how we understand our own sleep comes down to bias and perception. If you sleep through something, you don't remember it. You only remember the times you woke up, yet some people use that to \"prove\" that every little noise sets them off. You normally cycle through four stages of sleep every night. At NREM 1, you are right in the fuzzy grey zone of awake and asleep. Your brain is still aware of a lot of external surroundings (sounds, sleeping next to someone who tosses and turns all night) and you are easy to wake up in that stage. When you hit NREM 3, you are pretty much dead to the world, scientifically speaking. It takes a lot to wake you up, your brain really wants to ignore everything, and if you do wake up in this stage, you will feel gross and kind of out of it. Since you hit these stages more than once a night, you will naturally be more awake or more asleep at various points in the night. That's normal and healthy. People naturally spend less time in NREM 3 and REM sleep as they get older. People who experience hypervigilance (as in subclinical anxiety problems, anxiety disorders, or disorders related to trauma like PTSD) are \"scanners.\" This (a) has a *huge* impact on quality of sleep, and (b) makes them very sensitive to any sort of sleep disturbance, which makes the problem seem a lot bigger than it really is because it means interpreting normal sleep functions (hitting light sleep stages during the night) as a problem or threat. That there are tons of sleep disorders, mental illnesses, physical illnesses, etc. out there that mess with normal sleep architecture, so for those people, they may spend more time in light sleep stages or otherwise find their sleep getting a bit messy and therefore be more likely to wake up. Some sleep medications (especially benzos and z-drugs like zopiclone) also mess up sleep architecture, ironically. Regular old alcohol and other drugs can have similar effects. ETA: If you consistently have poor sleep, talk to your doctor!"
] |
[
2783
] |
[
[],
[],
[
"http://www.pnas.org/content/102/43/15676"
],
[],
[],
[],
[],
[],
[],
[],
[
"https://www.reddit.com/r/explainlikeimfive/comments/6apl75/eli5_why_are_some_people_light_sleepers_and/"
]
] |
[
"url"
] |
[
"url"
] |
|
a52ian
|
How does an automatic focus camera work? How does it "know" what to focus on? Compared to a manual focus of the same "type/parameters" and assuming everything else is identical with no special lenses/filters, etc., which one is inherently better than the other, quality-wise?
|
Technology
|
explainlikeimfive
|
[
"ebjgv8q"
] |
[
"Most of this is explained [here]( URL_0 ) so I'll paraphrase what was written there. Light travels into the camera through lenses, where it hits a series of Light Sensitive components. These components allow the camera to see that light as an image represented by dots, or pixels, each with their own distinct RGB color value. When an image is correctly in focus, the definition between two pixels will be clearly defined, especially if they are two different colors. If the image shows a red dot, then a blue dot next to it, the camera knows it's probably in focus because the two dots aren't purple-ish. For it to find this level of focus, it starts by scaling the focus in one direction in tiny steps, quickly analyzing a group of pixels (typically around a pre-defiend focus point, usually the center of the screen) to see if their difference in color is sharper than before, and keeps going until it stops seeing a difference, then it starts going back until the image starts getting worse. It'll then go back and forth like this until it's confident that it's gotten the best result it can. This is pretty much the same way as how an optometrist works when they test your vision (asking which is better, 1 or 2, etc). A manual focus is usually better and what most professionals rely on, as automatic focus can be grossly inaccurate (like sometimes when a digital camera picks a group of pixels to focus on that you didn't want it to focus on)."
] |
[
5
] |
[
[
"https://www.reddit.com/r/explainlikeimfive/comments/vkgku/eli5_how_does_a_camera_know_when_an_object_is_in/"
]
] |
[
"url"
] |
[
"url"
] |
|
62rdh0
|
Why do people get sleepy and / or eat when they get bored?
|
Other
|
explainlikeimfive
|
[
"dformpl"
] |
[
"Think of it as evolutionary to survival. If you aren't doing anything, those are the things you should catch up on so if you do have to fight for your life, your ready to go."
] |
[
5
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
aumqzq
|
Why does allergy to a specific food decrease over the age?
|
Biology
|
explainlikeimfive
|
[
"eh91vk1"
] |
[
"It usually doesn’t. Can you be more specific? Most of the time, allergies get progressively worse the more times someone is exposed to the allergen"
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
i23l0h
|
Why do lemons have seeds but limes don't?
|
Biology
|
explainlikeimfive
|
[
"g01r58f",
"g01r3wm",
"g01jjbp"
] |
[
"Persian limes (not Key limes) are seedless. They can produce fruit without being fertilized. They are generally grafted instead of grown from seed. Limes like these at the grocery store all perhaps come from the same \"tree\" sliced into bits and surgically attached Frankenstein style to different plants. Freaky if you think about it."
] |
[
96
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
5r4dig
|
Why is the kitchen staff excluded from receiving tips?
|
Culture
|
explainlikeimfive
|
[
"dd4c9q0"
] |
[
"They're not paid wait staff salary. Plain and simple. Wait staff members, bar keep, and bus persons are kept at a lower wage and because of this, their earning is heavily reliant on tipping as a result of their excellent service. Remember, the next time someone comes by the table and tries to make sure you have everything you need, that person is probably making around $4/hr as a base salary and depends on you leaving at least double the tax."
] |
[
8
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
a0lf7l
|
Do cosplay shows have a "don't" list for cosplay effects?
|
For example, I'm assuming most consortium rules would state that your cosplay can't have an effect that expels real fire from it. But do these places have an actual list or do they just assume cosplayers use their own judgement? I remember a month ago, a Halloween goer got arrested, because their costume included real, unfired, shotgun shells around their chest.
|
Culture
|
explainlikeimfive
|
[
"eaiipnq",
"eaik2i5",
"eaii51s",
"eaiiim5"
] |
[
"Fan conventions generally have a weapons policy. I went to a con once, and their policy allowed fake bladed weapons and fake firearms, but they needed to be inspected and marked. They also allowed real bladed weapons, which had to be inspected, marked, sheathed and securely fastened to the sheath so they couldn't be drawn. \"Real projectile weapons\" were not allowed, and this included Nerf guns, squirt guns, and anything that fires any sort of solid, liquid or gas."
] |
[
27
] |
[
[],
[
"https://www.fanime.com/rules/weapons-policy/"
],
[],
[]
] |
[
"url"
] |
[
"url"
] |
9m8ds8
|
Why do you feel incredibly cold when your body is actually burning hot when you are sick and vice versa?
|
Biology
|
explainlikeimfive
|
[
"e7cqrqr"
] |
[
"When you are sick with something like the flu, the bodies natural defense is to raise your body temperature to help kill off invading bacteria/viruses. The feeling of being cold is your blood temperature being colder than your bodies new set point"
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
5wq70f
|
Do editors at big movie studios use commercially available software (Premiere, etc) to edit big budget movies or do those studios have proprietary software they use?
|
Technology
|
explainlikeimfive
|
[
"dec4gts"
] |
[
"Avid is the most popular choice or sometimes Final Cut Pro(I think that one has become less popular). Those are both commercially available, although they're a little pricey."
] |
[
6
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
jkhbd5
|
How/Why does benadryl work for dystonic reactions?
|
ELI5 So. im studying for a neurology test, and ive got a question in my head i cant seem to find the answer to. the only answer i can find is the *indications* *to* **GIVE** *benadryl* when a pt in the feild has a dystonic reaction, or ataxia secondary to SSRI/tricyclic antidepressants/Anti psychotic reactions. *i know benadryl acts as an inverse agonist at the H1 receptor(cellular migration, nociception, vasodilatation, and bronchoconstriction), reversing effects of histamine on capillaries, reducing allergic reaction symptoms(ie:uticaria). * benadryl acts as an intracellular sodium channel blocker, resulting in local anesthetic properties. but me no get why magic pink pill fix jumpy muscles?
|
Biology
|
explainlikeimfive
|
[
"gaj6e6f"
] |
[
"First generation H1 antagonists are also anticholinergics. Typical antipsychotics block central dopamine receptors which causes a rise in cholinergic output - the cause of the dystonic reaction. So how do you treat this: with a medication with anticholinergic properties such as benztropine or diphenhydramine because they block central muscarinic receptors."
] |
[
7
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
czs6eg
|
what makes a country non democratic?
|
Other
|
explainlikeimfive
|
[
"ez0jneh",
"ez0kwta",
"ez32sq9"
] |
[
"The elections aren't \"fair and square\". They are basically just for show. Saddam Hussein also had elections, and was consistently re-elected with 100% of the vote."
] |
[
19
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
f0zl90
|
why do kitchen scissors have middle teeth?
|
Why do kitchen scissors have those metal teeth in the middle?
|
Engineering
|
explainlikeimfive
|
[
"fh0n70m",
"fh0mfen"
] |
[
"Are you talking about above where you grip? That's used to crack nuts, lobtser/crab shells or grip to open small bottles. Some kitchen scissors have many tools on it (like the end being a flathead screwdriver, or a bottle opener for pop)"
] |
[
3
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
g8pffq
|
What do people mean when they describe sports prospects having a low/high floor or low/high ceiling
|
Other
|
explainlikeimfive
|
[
"foosfoh"
] |
[
"The floor is the minimum contribution that the player will have. The ceiling is the maximum potential that a player could have. A college player that has great natural talent but crap technique has a high ceiling, a player with horrible natural ability but a great technique an desire has a high floor, bit low ceiling."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
f81v8q
|
what exactly is an accrual ? What are contra asset accounts
|
Economics
|
explainlikeimfive
|
[
"fiicepx",
"fiiz12t"
] |
[
"Accurals are when you are acknowledging the liability without actually making a payment. (Salaries Accrued). Contra Asset are used to for reductions of assets so that net amount can be reported. (Accumulated depreciation)."
] |
[
3
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
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